docs: def _maybe_drop_message(self):
          """Check to see if processing this message would exceed the configured
          error max retry value. If so, if a drop exchange is configured, publish
          to that. Finally, raise :exc:`DropMessage`.
  
          :raises: rejected.errors.DropMessage
  
          """
          if self.headers[_PROCESSING_EXCEPTIONS] >= self._error_max_retry:
              self.logger.warning('Dropping message with %i deaths due to '
                                  'ERROR_MAX_RETRY',
                                  self.headers[_PROCESSING_EXCEPTIONS])
              if self._drop_exchange:
                  self._republish_dropped_message('max retries ({})'.format(
                      self.headers[_PROCESSING_EXCEPTIONS]))
              raise DropMessage